Isihp-2S/2U Serial Card - Multitech ISIHI-2S User Manual

1.1.1 ISIHP-2S/2U Serial Card

The ISIHP-2S/2U and ISIHI-2S/2U cards each offers eight RAS ports using two Basic Rate Interface (BRI)
ISDN lines; the ISIHP-4S/4U has 16 ports using four BRI ISDN lines. The eight ports of the 2S/2U models
allow a server to accept any combination of analog modem and digital ISDN calls, making a maximum of four
simultaneous independent data connections (sessions). For the ISIHP-4S/4U, its sixteen ports allow a server
to accept any combination of analog modem and digital ISDN calls, making a maximum of eight simultaneous
independent data connections. This arrangement gives the user the flexibility to customize the settings of the
terminal adapters and modems. The terminal adapters on the ISIHP-4SD can make eight simultaneous
independent connections.
From the perspective of the server PC, the ISIHP-2S/2U (or ISIHI-2S/2U) is an eight-port serial card with eight
devices permanently attached to the serial ports (Figure 1-1).
The first four ports are the two terminal adapters, each of which appear as two ports. The remaining four ports
are the four central site modems. The following table summarizes the correlation of ports and devices.
Table 2: 2S/2U Ports and Devices
2S/2U Device ISDN Line
Port # Number
1 TA
2 TA
3 TA
4 TA
5 Modem
6 Modem
7 Modem
8 Modem
Com Ports
5
Modem
1
2
6
Modem
7
Modem
3
4
8
Modem
Figure 1-1. Modems and Terminal Adapters
of ISIHP-2S/2U and ISIHI-2S/2U.
1
1
2
2
1
1
2
2
ISDN
RJ-45 jack
TA
Line 1
RJ-45 jack
TA
Line 2
Chapter 1 - Introduction
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